Vacuum fuel-feed device.



L. BERG.

VACUUM FUEL FEED DEVICE.

APPLICATION FILED SEPLJO. x917.

1 'y y fi fio Patented Sept. 3, 1918.

- understood manner.

LOUIS BERG, OF CHICAGO, ILLINOIS, ASSIGNOR TO STEWART-WARNER. SPEEDOMETER CORPORATION, OF CHICAGO, ILLINOIS, A CORPORATION OF VIRGINIA.

VACUUM FUEL-FEED DEVICE.

LZTKGSS.

Specification of Letters Patent. Patenteql Se t, 3 1&18,

Application filed September 10, 1917. Serial No. 190,680.

To all whom it may concern:

Be it known that I, LOUIS BERG, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Vacuum Fuel-Feed Devices, of which the following is a specification, reference being had to the accompanying drawings, forming a part thereof.

The purpose of this invention is to provide an improved construction in a vacuum fuel feeding devicefor internal combustion engines, the specific purpose being to afford a simpler means than has heretofore been used for alternating the domination of the suction and atmospheric pressure in the vacuum chamber of such a device. It consists in the elements .and features of construction, shown and described, as indicated in the claims.

In the drawings, which show a modification of an invention which is shown in another form and claimed broadly in my copending application, Serial No. 190,678:

Figure 1 is a diagrammatic view presenting the main elements of the invention in their general relation as assembled on an automobile.

Fig. 2 is a vertical axial section of the vacuum feed device proper, showing the several elements in the vacuum chamber at the position occupied during filling,-that is,

during the domination of the suction.

Fig. 3 is a view similar to Fig. 2, showing the position of the parts during emptying of the vacuum cl1amber,-that is, duringthe domination of the atmospheric pressure.

In the structure shown in the drawings 1 is thelow-level main fuel supply tank from which the fuel supply is led by aconduit, 3, to the vacuum chamber, 2, of the vacuum feed device, from which it is delivered by gravity through the discharge duct, 4, past the check valve, 5, into the reservoir or reserve chamber, 6, from which it is supplied to the carbureter by gravity in the well The vacuum chamber, 2, has a suction connection, 7, leading to the intake manifold of the engine, and an atmosphere inlet port, 9, at the top of the said vacuum chamber, which is controlled by an atmosphere inlet valve, 10, seating upwardly. The valve, 10, is formed at the upper end of a vertical stem, 10, which obtains guidance at its lower end in a sleeve,

11*, which forms the lower end of a hanger, 11, depending from the top plate, 12, of said yacuurn chamber. On said sleeve, 11, there is guided for vertical movement a lower buoy, 13, and on the valve stem, 10*, there 1s similarly guided a larger upper buoy, 14. Upon the hanger, 11, there are fulcrumed two bell-crank levers, 15, 15, having their outwardly-downwardly extending arms, 15*, engaging with apertured ears or eyes, 13*, which are formed upon opposite ends of a plate, 13?. mounted rigidly upon the top of a buoy, 13, whereby said levers are actuated by and actuate said buoy, 13. Said levers engage an annular flange, 10", on the valve stem, 10, by means of apertures, 15, in said levers respectively. Said levers have up standing arms, 15, at opposite sides of the valve stem, 10, and the upper buoy, 14, has a downwardly-extending projection or hub, 14*, which is adapted to enter between said upstanding arms for a certain purpose, hereinafter explained'and which terminates 1n an abrupt downwardly-facing shoulder at which said up-standing arms run off said hub when the upper float rises, as hereinafter more particularly explained.

The operation of the structure described may be understood from the foregoing description thereof, but will be further explained.

Starting with the vacuum feed device empty of liquid, the vacuum chamber being connected with the intake manifold by the pipe, 7, and the engine operated, a partial vacuum is produced in the vacuum chamber by the suction stroke of the engine piston causing liquid to be forced up from the low level tank, 1, into said vacuum chamber. It will be understood that at the beginning of the operation both the buoys, 13 and 14, being at their lowest position, the valve, 10, will be held closed by the down weight of the lower buoy, 13, and locked in that position by the engagement of the hub, 14*, of the upper buoy between theup-standing arms, 15-, of the levers, 15. As the liquid rises in the vacuum chamber, it will tend to uplift the lower buoy, 13, but this will be prevented by the locking action of the hub, 14, of the upper buoy, as above described, and no movement of the valve, 10, will occur until the liquid has risen far enough to uplift the upper buoy, 14, withdrawing its locking hub, 14, from between the upstanding lever arms,

sure thus admitted quickly dominates the suction and causes the liquid in the vacuum chamber to fall therefrom and pass the check valve, 5, into the reservoir, 6. lVhile this action is going on, it will be observed that .the upper float, 14, is held locked at its upper position by the engagement of the upper end of the upstanding lever arms, 15*, under the abrupt shoulder of the hub, 14, and that in any event, said buoy, 14, has no operative connection with the valve by which it could move it upon either rising or falling. The atmosphere inlet valve, 10, therefore remains open until the liquid level in the chamber has fallen so farthat the lower buoy, 13, being in large part out of the liquid, ceases to be upheld by the liquid, and falling, actuates the levers, 15, causing them to thrust upward the stem, 10, and close the valve, 10, at the same time spreading the upper upstanding arms of said levers, so that the hub, 14*, of the upper float which has been resting upon their upper ends, drops between them,sa1d float, l4, falling,and locks the levers as in the first condition, the slight taper of said hub, 14, operating to wedge the upstanding arms of the levers, 15, apart, and cause said levers to crowd the valve, 10, snugly to its seat. The condition is now as at the beginning, and the cycle of action described will be repeated. The engagement of the fork, 15, of the lever with the flange, 10 is of course loose enough to permit the shifting from the slightly oblique position of the engagement seen in Fig. 2, to the oppositely slightly oblique engagement seen 1n Fig. 3; and this degree of looseness permits the movement of the levers which occurs during the withdrawal of the slightly tapered projection, 14 from between them to occur without any r sulting movement of the valve.

I claim 1. In a vacuum fuel feeding device for intarmac ternal combustion engines, in combination with a main low level liquid fuel supply tank, a vacuum chamber at a higher level and a conduit for liquid fuel from the said tank to'the vacuum chamber, the vacuum chamber having a liquid fuel outlet and a valve adapted to be opened by gravity flow of the liquid through said outlet, and to be held on its seat by suction in the vacuum chamber, the vacuum chamber having a suction connection and an atmosphere inlet port, a valve which controls said atmosphere inlet port seating upwardly; a fixed support in the vacuum chamber by which the stem of the atmosphere valve is guided in its seating and unseating movement; a lower and an upper buoy in the chamber, the lower buoy being guided on said support, and the upper buoy being guided on the valve stem; a lever fulcrumed on said support operatively connected with the lower buoy and operatively engaged with the valve stem and having a lever arm extending upward from the fulcrum, the upper buoy having at its lower side a projection which engages the upwardly extending arm of the lever when said upper buoy descends along the valve stem, and locks said lever at position for holding the atmosphere inlet valve seated, said projection having at its lower end an abrupt shoulder permitting an abrupt movement of the lever when the upper buoy rising carries said shoulder to the end of said lever arm.

2. In a construction such as set out in claim 1 foregoing, said projection from the upper buoy being tapered, whereby it is adapted to operate with a wedging action-upon the lever when the buoy falls, to force the atmosphere valve to its seat by said falling of said buoy.

3. In a construction such as set out in claim 1 foregoing, the engagement of the lever with the valve stem being loose, permitting slight plav, whereby the initial movement of the lever during the disengagement of the tapered projection with the lever is without effect upon the valve.

In testimony whereof, I have hereunto set my hand at Chicago, Illinois, this 30th day of August, 1917.

LOUIS Base. 

